Treating emulsions



i It has been heretofore preparation of the a '25 hydrocarbon-sulphonic acids.

cially for instance sodium chloride or an autoclave they can are apparently insoluble in water.

been used,

until the material be finall Patented May s, 1928.

UNlTED srA'rss PATENT OFF 1,668,941, ICE.

' P LOUIS BURGESS, OE BAYONNE, NEW JERSEY, ASSIGNOR TO STANDARD. OIL DEVELOP- MEN! COMPANY, A CORPORATION OF DELAWARE.

No Drawing.

This invention relates to the art of treating emulsions of hydrocarbon oils and water, and will be fully understood from the following description. proposed to treat, for the purpose of breaking, the emulsions commonly occurring in refinery practice, by means of sodium salts of sulphonic acid. is procedure necessitates a particular gent and in practice oflers inconveniences. I have now discovcred that the sulphonic acids, as derived from sludge of hydrocarbon oils which have been refined with fuming or concentrated 15 sulphuric acid, accomplish an improved result in the breaking. of emulsions.

Sludges se arated from hydrocarbon oils, particularly ubricating oils, after treating with fuming sulphuric acid or the anhy- 20 dride S0,, ordinarily quite largely consist of hydrocarbon-sulphonic acids. Sludges also erived by treating such ,oils with concentrated sulphuric acid, not fuming, also may contain substantial percentages of The petroleum-sulphonic acids referred to however, wherever found, may be identified by their characteristics. They are soluble in water buteasily salted out by electrolytesi1 espedrochloric acid. They .are not easily hydrolized and are stable in boiling solution; but

I by heating with mineral acids at temperatures as high as 180 C. under' pressure in be broken down with formation of sulphuric acid and neutral hydrocarbons. the salts of, the alkalis being very soluble in water, while the calcium and aluminum salts In "proceeding in accordance with this invention the sludge' separated from a treated oil, such as a lubricating oil, where fuming or concentrated sulphuric acid has preferably the sludge from fum- 111 acid treating, is purified to obtain the sui phonic acids, for example by washing with hydrochloric acid diluted for instance i to about 10%, the washing being repeated is substantially free from The hydrochloric acid may fy removed by pressing or evaporation. I desired, instead of washing directly withthe diluted acid the sludge can sulphuric acid.

- .be dissolved in water and then be precipi- They form. salts with bases,

Application filed March 20, 1923. Serial No. 626,378.

tated out by hydrochloric acid, these steps being repeated until the material is sub-. stantially free. from sulphuric acid. To the emulsion to be treated there is then added sulphonic acid purified as described in the foregoing, using a proportion of about onefourth to five percent or more by "volume. The precise character of the oil emulsion will determine the best proportion to be used, more refractory emulsions requiring of course more of the acid. The mixture is now preferably heated, in an acid resistance receptacle the temperature being raised to 100-212' The heating isnot absolutely necessary, but for average concentrations of the sulphonic acid will accelerate the separation. In case heating is not desired the percentage of sulphonic acid should be considerably increased to obtain results within practicable time limits. ample, a se aratpr slop emulsion is treated. with 2% o sulphonic acid, introduced for instance in the form of a 20% aqueous solution, and the mixture is heated up to about 170 F. On standing the mass separates into two layers, the upper of which is oil and the lower water and dirt.

It will be understood, of course that field emulsions may be treated in accordance with this process as well as refinery emulsions.

In the appended claims I have used the term strong sulfuric acid as generic to all concentrations of sulfuric acid, including fuming acid, which will produce mineral oil sulfonic'acidssuitable for the purpose herein defined.

What I claim is:

As a specific ex- 1. The improvement in the art of treat- 3 ing emulsions of hydrocarbon oils and water, i which comprises addin thereto one-fourth to five percent of sulp onic acid obtained from sludge of lubricating oil refined with strong sulphuric acid, then heating the mixture to about 170? F.

2. The improvement in the art of treating emulsions of hydrocarbon oils andwhich comprises addin acid obtained from slu ge of hydrocarbon oil refined with strong sulphuric acid, in the proportion of one-fourth to five percent and hea'tin the mixture.

3. T e improvement in the art oftreating emulsions o hydrocarbon oils and water, which comprises adding thereto a sul water,-. thereto sulphonic of a Water soluble sulphonic acid derived from the refining of hydrocarbons with strong sulfuric acid.

6. Method according to claim 5, in which the water soluble sludge sulfonic acid,is 15 derived from the treatment of hydrocarbon oil with fuming sulfuric acid. 1

7. Method according to claim 5, in which the mixture of the oil to be treated and the sulfonic acid is heated to a temperature of 20 at least 100 F.

LOUIS BURGESS. 

